Hydraulically controlled graining machine manipulating device



c. zARKlN 2,413,898 HYDRAULICALLY'CONTROLLED GRINING MACHINE MNIPUL'ATING DEVICE Jan. 7, 1947.

Filed Feb` *1, 1943 2 Sheets-Sheet 1 2 Sheets-Shag?. 2 y

Jan. 7, 1947. c. zARKlN HYDRAULICALLY CONTROLLED GRAINING MACHINE MAN'IPULATING DEVICE Filed Feb. 1, 194s xl. H 5% Afll 1 ul ...E l.

Patented Jan. 7, 1947 UNITED sTATEs PATENT oFEicE HYDRAULICALLY CONTROLLED GRAINING MACHINE MANIPULATING DEVICE Charles Zarkin, New York, N. Y.

Application February 1, 1943, Serial No. 474,364

1 Claim. l

The invention herein disclosed relates to the graining of printing plates.

Special objects of the invention are to provide power means for tilting the graining tub and for operating the dumper, instantly available at any time during operation of the machine and to provide convenient controls bywhich such power mechanism may be regulated as required.

Other desirable objects will appear as the specication proceeds.

The drawings accompanying and forming part of the following specification illustrate one practical commercial embodiment of the invention, but it is realized that the actual structure may be modified and changed in various respects, all within the true intent and broad scope of the invention as hereinafter dened and claimed.

Fig. 1 in the drawings is a side elevation of one of the graining machines, with portions broken away and appearing in section.

Fig. 2 is a broken sectional and partly diagrammatic View illustr-ating the hydraulic power and control system.

The graining machine illustrated is of the single eccentric type covered in Zarkin United States Patents 1,718,020, June 18, 1929; 1,935,- 306, November 14, 1933; 1,960,447 May 29, 1934; and 2,074,633, March 23 1927, involving a graining tub 5, pivotally mounted at one end at 5, on a sub frame 1, supported on balls 8, and guided for oscillatory movement by a diamond frame" 9, slidingly guided at I0, on the base H, and slidingly connected with the sub frame at I2.

A motor I3., mounted in one corner of the base, through belting I4, drives a vertical shaft (not shown) at the center of the machine carrying a crank or eccentric in its upper end in driving engagement with the tub supporting frame 1.

A hydraulic jack I5, is supported on a step I6, at the end of the sub frame opposite the Vhinge 6, and fluid under pressure is supplied to and exhausted from this jack through pipe I'I.

The pressure source for the operating iluid is shown as a rotary pump I8, carried by a bracket I9, secured at 20, over a lower flange of the base frame, adjacent the motor and having a pulley 2 I, driven by belting 22, from an additional pulley 23, on the lower end of the motor shaft. This pump thus will be driven while the motor which operates the machine is running and the pressure fluid therefore will be available at all times while the machine is in operation.

A tank 24 is shown mounted in the base of the machine and the pump is shown connected with this tank by a supply line 25.

From the pressure side of the pump, a line 2E, is shown extending to the inlet side of the dumper control valve 2l, and another line of piping 28, is indicated extending from that valve to the pressure inlet side of the hand valve 29, controlling the tub raising and lowering movements.

The two control valves 21 and 29, may be of similar construction and they may be located where most convenient for operation by one observing the eiect of these two controls.

The tub control valve 29, is shown mounted on the base and the dumper control valve 2l, is shown mounted on one of the side frames 30, on which the dumper 3l, is pivoted at 32.

The handles 33, 34, of these two valves are shown as balanced by springs 35, to stand in the centered neutral positions indicated and in which relation the pump simply circulates the oil or other liquid back to the reservoir tank 24, such flow being as indicated in Fig. 2, from tank 24, by the line 25, to the pump, from the pump by line 26, to valve 21, then by line 28 to valve 29, and back through return line 36, to the tank.

If the tub is to be raised, the handle 33, is rocked to the left to cause cam 3l, moving with the handle, to close valve 38, and thus shut oit return of liquid to the tank through the lines 36. Liquid under pressure coming from line 28, will then open the spring closed check valve 39, and pass through the tubing or flexible hose Il, to the tub lifting ram I5.

On releasing pressure on valve handle 33,'the springs 35, will restore this handle and hence the cam 3l, to the central position, Fig. 2, where valve 38, will open to continue return of liquid under pressure to the tank through line 36, and the check valve 39, will hold the pressure in the ram and thus keep the tub supported at any desired angle of inclination.

To lower the tube or return it to horizontal position, the handle 33, is rocked to the right, Fig. 2, to cause the cam 31, to open up the return valve 38, and to cause plunger 40, to open check valve 39, and exhaust the liquid from the ram through line I1, and which liquid can then escape by transfer passage 4I, and the open valve 38, back through line 33, to the tank.

Under all these conditions, the pump can continue in operation.

The ram for operating the dumper is shown as comprising a piston element 42, having a ball bearing mounting 43., on its lower end and a cylinder 44, sliding over the upper end of said piston element and pivotally connected at 45, with a crank 46, on the end of the dumper shaft 32.

By reference to Fig. 2, it will be seen that raising the control handle 34, will have the effect of rocking the cam 41, to close the relief valve 48, and cause the liquid coming from the pump through line 26, to ow by way of the transfer passage 49, check valve 50, and flexible tubing 5I, into the ram cylinder 44, above the piston 42. Release of this handle at any time will permit the springs 35, to return and hold the handle in the neutral position shown, where the liquid admitted to the ram will be trapped by the check valve 50, and the ram thus will then hold the dumper in the position to which it has been raised.

To lower the dumper, the handle 34, is depressed and this, through the cam 4T, will lift the plunger 52, to open check valve 50, and exhaust the pressure liquid from the ram cylinder, such liquid then returning by transfer passage 49, piping 23, and return line 36, to the tank.

To enable quick lowering of the dumper, free of back pressure and any delay that might be occasioned by flow of released liquid back through the lines 28 and 36, and the tub control valve 29, a quick return line 53, is shown provided from the top of the ram cylinder 44, to the tank 24, and including a normally closed quick release valve 54, which can be instantly opened at any time by a trip lever 55.

The dumper 3|, is shown as of the type covered in Zarkin United States Patent 2,074,633, involving a trough-like receptacle, which can be lowered to receive the marbles, balls or other graining elements from the tub and which can be raised to lift the graining elements and discharge them back into the tub.

The connection of the two control valves in series with each other and in series with the pump and tank provides a complete supply and return hydraulic circuit, in which the pump may operate continuously and either valve be actuated at any time to shut off return and direct al1 pressure to either the ram for raising the tub or the ram for operating the dumper.

What is claimed is:

A graining machine comprising in combination, a graining tub mounted for graining movements and for raising and lowering, a dumper mounted for raising and lowering movements at one end of said tub, a hydraulic jack for raising and lowering said tub, a second hydraulic jack 4 for operating said dumper, means for maintaining circulation of liquid under pressure in a continuous closed circuit providing liquid supply and return flow connections, a control valve for controlling operation of the tub raising jack and a second control valve for controlling operation of the dumper operating jack, said control valves being interposed in said liquid flow connections and each having normally open supply and return flow passages affording normal continuous supply and return ow of liquid through the circuit, the rst control valve having a branch supply and return connection extending to the tub raising jack and a normally closed check valve for holding liquid supplied through said branch connection, said check valve being in communication with the passages and exposed to the pressure within said valve, the second control valve having a branch supply and return connection extending to the dumping jack and a normally closed check valve for holding liquid supplied through said branch connection, said check valve being in communication with the passages and exposed to pressure within said valve, a valve element in the rst control valve movable in one direction to close the return ow passage and thereby cause the supply flow of liquid to force the check valve open and pass through the branch connection to the jack controlled by that control valve and movable in the opposite direction to open said return low passage and to open said check Valve to exhaust liquid from said jack back through said opened return flow passage, a similar valve element in the second control valve movable in one direction to close the return ow passage in that valve and movable in the opposite direction to open said return ow passage and to open the check valve in the branch supply and return connection extending from that control valve, means for yieldingly holding said valve elements balanced in neutral position maintaining said supply and return flow passages in open condition, said control valves being connected with their supply and return flow passages in series relation so that return iiow from one valve may normally be through the other valve and a quick release return connection from the jack controlled by said one valve back into the circulation system, independent of said normal return ow through the other valve and thereby adapted to quickly release liquid from said jack free of control exercised by said other'series connected valve.

CHARLES ZARKIN. 

